JP2009256734A - Laminated steel plate, and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a steel plate realizing high workability which has not been obtained heretofore, jointly realizing the increase of strength, the improvement of roughening resistance and the improvement of corrosion resistance, and having similar qualities even in the plate thickness of 5 to 10 mm, and to provide a method for producing the same. <P>SOLUTION: A plurality of steel plates are prepared, and a second layer is stuck at least to one side of a part or the whole of the plurality of steel plates, wherein, the second layer is a metal essentially consisting of a component other than Fe. Thereafter, rolling is performed, and heat treatment is performed, so as to recrystallize the steel plates. In this way, the accumulation degree of the ä222} face of the obtained laminated steel plate is remarkably made high, so as to improve its workability. Further, by selecting the kind of each layer in the laminated steel plate, high workability which has not obtained heretofore is realized, and also, the increase of strength, the improvement of roughening resistance and the improvement of corrosion resistance are jointly realized. Further, these excellent qualities can be realized in a thick steel plate whose plate thickness exceeds 5 mm. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a laminated steel sheet having a high {222} plane integration degree and a manufacturing method thereof.

  Steel sheets used for automobile bodies, parts, household appliances, building materials, etc. are required to be high-strength steel sheets so that sufficient strength can be ensured even if the sheet thickness is reduced and the weight is reduced. On the other hand, in these applications, since the steel sheet is processed into the desired shape by press forming, deep drawing, etc., excellent workability that can be performed without generating cracks and wrinkles is required. Yes. Also, in most cases, in order to paint the surface of the steel sheet, that is, in order to obtain good paintability, the surface of the steel sheet is not roughened even if it is formed, and the rough skin resistance is also required. At the same time, there are applications that require excellent corrosion resistance.

  Patent Document 1 adjusts the contents of Nb and C, has a specific (222) accumulation degree, has a high strength with a tensile strength of 440 MPa or more, and an average r value (Rankford value) of 1.2 or more. A high-strength steel sheet excellent in deep drawability is described. Cited Document 2 describes a thick cold-rolled steel sheet having a sheet thickness of 1.2 mm or more and an r value of 2.9 or more. Cited Document 3 describes a high-carbon cold-rolled steel sheet that reduces fluctuations in the deep drawing height that occurs during forming and simplifies the part processing process. Cited Document 4 describes an ultra-low carbon cold-rolled steel sheet that achieves both rough skin resistance and workability.

  It is said that the workability of the steel sheet depends on the texture of the αFe phase and the γFe phase, and can be particularly improved by increasing the degree of {222} plane integration of crystals on the steel sheet surface.

  Patent Document 5 relates to a high-strength cold-rolled steel sheet and a hot-dip galvanized steel sheet, and each amount of Si, Mn, and P contained in the steel sheet is determined by a {222} plane and a {200} plane parallel to the plate surface. It is shown that the deep drawability of the steel sheet can be ensured by controlling based on a certain formula between the ratio of the X-ray diffraction intensities. However, there is no indication of the effect of plating applied to the surface on the texture.

  Patent Document 6 relates to a high-strength cold-rolled steel sheet for enamel and a method for producing the same. Here, the (111) texture is controlled by defining the amount of Nb added by the amount of C contained, and further by defining the conditions for hot rolling and cold rolling.

Patent Document 7 relates to an alloyed hot-dip galvanized steel sheet and a method for producing the same. Of the X-ray diffraction intensities, when the ratio of {200} plane intensity to {222} plane intensity, I (200) / I (222), is less than 0.17, streak pattern defects are not generated on the plating surface. When the finish rolling temperature of hot rolling is Ar ₃ + 30 ° C. (temperature at which ferrite transformation starts during cooling + 30 ° C.) or higher, the X-ray diffraction intensity ratio, I (200) / I (222) is 0.17. The finding that it is less than is shown. However, it is not shown that the texture of the steel sheet is controlled by applying plating.

  Patent Document 8 relates to an ultra-low carbon cold-rolled steel sheet having excellent workability and rough skin resistance. It is an ultra-low carbon cold-rolled steel sheet having a C content of 0.01% or less by weight% in steel, and the ferrite grain size No. A, the ferrite grain size No. of the inner layer occupying 1/2 of the total thickness centering on the thickness center. Where a−b ≧ 0.5, a ≧ 7.0, and b ≦ 7.5 are satisfied, and the ratio I (222) of the diffracted X-ray intensity from the {222} plane and the {200} plane is satisfied. ) / I (200) is controlled to 5.0 or more at 1/15 of the total plate thickness from the surface of the steel plate and to 12 or more at the center of the plate thickness of the steel plate, thereby roughening the surface of the steel plate during press molding. It could be reduced.

  As described above, in order to improve the workability of the steel sheet, a method for improving the {222} plane integration degree of the αFe phase and the γFe phase has been devised, and the steel plate component, rolling conditions and temperature conditions have been optimized. I came.

  Further, in Patent Document 9, a high Al-containing steel sheet having an Al content of 6.5% by mass to 10% by mass and an αFe crystal {222} plane integration degree of 60% to 95%, or {200} plane integration. It is disclosed that when the degree is 0.01% or more and 15% or less, the workability can be improved even with a high Al content. Further, as a method for improving the degree of surface integration of the specific surface with a high Al content steel sheet, an Al alloy is formed on the surface of the base material having an Al content of 3.5% by mass or more and less than 6.5% by mass by a hot Al plating method , Cold rolling, and diffusion heat treatment are disclosed.

  On the other hand, a so-called clad steel plate in which different types of steel plates and metal plates are laminated is known. For example, Patent Documents 10 to 12 describe a clad steel plate in which carbon steel is used as a base material and a steel plate or a metal plate different from the base material is laminated.

  Patent Document 10 shows that a clad steel plate having excellent corrosion resistance can be obtained by using a low-carbon steel as a base material and stainless steel as a laminated material. Furthermore, by making the acid-soluble Al content of the low carbon steel in the range of 0.10 to 1.5% by weight, the workability of the resulting clad steel sheet can be improved, and the generation of wrinkles during processing can be suppressed. It is said.

  Patent Document 11 discloses a corrosion-resistant clad steel plate in which a corrosion-resistant metal plate is laminated on one side or both sides of a carbon steel plate using an amorphous alloy as a bander. It is also shown that titanium, zirconium, tantalum, niobium, nickel, copper and alloys thereof can be used as the corrosion resistant metal plate.

  Patent Document 12 discloses a clad steel plate in which carbon steel is used as a base material and the laminated material is stainless steel, a high Ni alloy, or a Ni-base alloy, and describes that the clad steel plate is excellent in toughness and corrosion resistance.

JP 2005-120467 A JP-A-11-5021 JP 2000-328172 A Japanese Patent Laid-Open No. 11-350072 JP-A-6-2069 Japanese Patent Laid-Open No. 8-13081 JP-A-10-18011 Japanese Patent Laid-Open No. 11-350072 JP 2006-144116 A Japanese Patent Laid-Open No. 11-77888 JP 2002-239741 A JP 2003-27140 A

  Conventionally, a technique for improving the {222} plane integration degree of the αFe phase and the γFe phase by optimizing the steel plate components, rolling conditions and temperature conditions has been devised to meet the needs for improving the workability of the steel plates. In Patent Document 9, a high Al content steel sheet having an Al content of 6.5% by mass or more and 10% by mass or less, and a {222} plane integration degree of αFe crystal is 60% or more and 95% or less, or a {200} plane integration degree. It was shown that the workability can be improved even when the Al content is high by setting the content of the steel to 0.01% or more and 15% or less.

  Steel sheets used for processing, including steel sheets for automobiles and steel sheets for home appliances, are required to improve workability beyond the level realized by the above-described conventional methods. Moreover, it is required to have both improved workability and higher strength. Furthermore, there is a demand for a steel sheet that has not only improved workability and high strength, but also has rough skin resistance that prevents the surface of the steel sheet from roughening even when it is formed, or excellent corrosion resistance. Naturally, these steel plates cannot be realized with a high Al content steel plate as shown in Patent Document 9.

  The steel sheet described in Patent Document 9 has a maximum thickness of 5 mm. On the other hand, in a thick steel plate having a plate thickness exceeding 5 mm, there is an increasing demand for improving workability.

  In addition, as described above, by using a clad steel plate, a functional composite that cannot be achieved by a single steel plate is made. In particular, as in Patent Documents 10 to 12, corrosion resistance can be imparted to the carbon steel plate by bonding the steel plate or metal plate having corrosion resistance using the carbon steel plate as a base material. In addition, workability is improved by adjusting the components of the base material. However, the conventional clad steel plate has a problem that peeling occurs at the laminated interface (cladding interface) when it is hard-worked, and there is a limit even if the workability is improved by adjusting the components of the base material. Further, there is a problem that the peeling at the laminated interface appears more prominently as the thickness of the clad steel plate increases.

  The present invention provides a laminated steel plate that can achieve high workability that cannot be achieved by conventional steel plates and clad steel plates, and that can be realized by combining high strength, improved rough skin resistance, and improved corrosion resistance, and a method for manufacturing the same. The purpose is to do. In addition, an object of the present invention is to provide a laminated steel plate capable of realizing high workability in a thick steel plate having a plate thickness exceeding 5 mm and a method for producing the same.

  The inventors of the present invention are laminated steel plates having a structure in which a plurality of steel plates are laminated and integrated, and by increasing the {222} plane integration degree of the laminated steel plates, peeling at the lamination interface is less likely to occur even when subjected to strong processing. It has been found that a laminated steel sheet having excellent workability can be obtained even if the thickness of the whole laminated steel sheet is increased. Furthermore, the present inventors prepared a plurality of steel plates in manufacturing the laminated steel plate, and attached a second layer, which is a metal mainly composed of other than Fe, to the laminated surface of the plurality of steel plates, Stacking the steel plates with two layers attached, rolling the superposed steel plates, and then applying heat treatment to recrystallize the steel sheet structure, {222} plane integration of the obtained laminated steel plates The degree of remarkably increased, the workability improved, and unprecedented high workability was realized, and the improvement of the rough skin resistance was also realized. Further, by selecting the type of each layer of the laminated steel sheet, high strength and improved corrosion resistance have been realized.

That is, the gist is as follows.
(1) A laminated steel plate in which a plurality of steel plates made of one or both of carbon steel and alloy steel are laminated and integrated, and one of the αFe phase or the γFe phase at both the steel plate surface and the thickness center of the laminated steel plate Alternatively, the {222} plane integration degree with respect to the steel plate surface is one or both of 60% or more and 99% or less, or the {200} plane integration degree with respect to the steel plate surface is 0.01% or more and 15% or less. Laminated steel sheet.
(2) The laminated steel sheet according to the above (1), wherein the carbon steel is at least one of ultra-low carbon steel, low carbon steel, medium carbon steel, or high carbon steel.
(3) The laminated steel sheet according to (1) or (2) above, wherein the alloy steel is stainless steel.
(4) The laminated steel sheet according to any one of (1) to (3), wherein the steel sheet of each layer constituting the laminated steel sheet is a steel sheet having an Al content of less than 6.5% by mass.
(5) One or more of Al, Ni, Si, Sn, V, and Zn compared to each adjacent layer steel plate in part or all of the laminated surface of each layer steel plate constituting the laminated steel plate and both surfaces of the laminated steel plate The laminated steel sheet according to any one of (1) to (4) above, wherein the element is concentrated.
(6) The laminated steel sheet according to any one of (1) to (5) above, wherein the thickness of the laminated steel sheet is 5 μm or more and 10 mm or less.
(7) The laminated steel sheet according to any one of (1) to (6), wherein the steel sheets of each layer constituting the laminated steel sheet are of the same type.
(8) A plurality of steel plates having a plate thickness of 10 μm or more and 10 mm or less are prepared, and a second layer of a metal having a component other than Fe as a main component is attached to at least one side of part or all of the plurality of steel plates. A method for producing a laminated steel sheet, comprising: laminating the steel sheets, rolling the laminated steel sheets, and then recrystallizing by heat treatment and simultaneously integrating the laminated steel sheets.
(9) The method for producing a laminated steel sheet according to (8) above, wherein the thickness of the second layer to be adhered is 0.05 μm or more and 1000 μm or less.
(10) The second layer includes Fe, Al, Co, Cu, Cr, Ga, Hf, Hg, In, Mn, Mo, Nb, Ni, Pb, Pd, Pt, Sb, Si, Sn, Ta, Ti (8) or (9), which contains one or more elements of V, W, Zn, and Zr, and contains as a main component any one of the elements described above except Fe. Manufacturing method for laminated steel sheets.
(11) The second layer contains Al, and the plurality of prepared steel plates have an Al content of less than 3.5% by mass, according to any one of (8) to (10), Manufacturing method for laminated steel sheets.
(12) The second layer does not contain Al, and the plurality of prepared steel plates have an Al content of less than 6.5% by mass, according to any one of (8) to (10), The manufacturing method of the laminated steel plate of description.

  Since the laminated steel sheet of the present invention has a high {222} plane integration degree, even if it is strongly processed, peeling hardly occurs at the laminated interface, and the processability is excellent. Therefore, the laminated steel sheet of the present invention can be easily processed into various shapes, and can be made into a thin foil by cold rolling. In addition, by selecting the type of each layer of the laminated steel sheet, it is possible to achieve high workability that has not been achieved in the past, as well as high strength, improved skin roughness resistance, and improved corrosion resistance. Furthermore, these excellent qualities can be realized in a thick steel plate having a plate thickness exceeding 5 mm. These are useful for various structural materials, functional materials, and the like such as outer plates of automobile parts and home appliance parts that require complex-shaped press molding. Further, in the method of the present invention, it is possible to easily manufacture a steel plate having a high {222} plane integration degree by simply replacing the process of existing equipment without creating new equipment. Therefore, the steel plate of the present invention can be easily manufactured at low cost.

  The steel sheet described in Patent Document 9 is a high Al-containing steel sheet having an Al content of 6.5% by mass or more and 10% by mass or less, and the {222} plane integration degree of the αFe phase is 60% or more and 95% or less, or {200} One or both high Al-containing steel sheets having a {200} plane integration degree of 0.01% or more and 15% or less. The production of this steel sheet is performed by heat-treating Al after adhering Al alloy to at least one side of the steel sheet containing 3.5% by mass or more and 6.5% by mass or less of Al, and applying cold working strain. Met.

  The inventors of the present invention have been engaged in technological development for further improving the {222} plane integration degree and have conducted various experiments. As a result, the metal to be attached to the steel plate is not limited to Al, and cold rolling (cold rolling) is performed while the second layer made of a metal other than Fe is attached to the steel plate, and then the steel structure is crystallized by heat treatment. It was discovered that {222} plane integration can be improved by recrystallization, and this phenomenon can be manifested by a special dislocation structure formed in the steel during cold rolling. Recrystallization nuclei that develop {222} plane texture from the dislocation structure are generated by the heat treatment. Furthermore, if the component system is such that the Al content of the steel sheet after recrystallization is less than 6.5% by mass, the recrystallization nuclei tend to be generated more frequently, resulting in higher {222} plane integration. A steel sheet having a degree has been obtained. By making the Al content of the steel sheet to which the second layer is adhered not more than 3.5% by mass, it is possible to produce a steel sheet having an Al content of less than 6.5% by mass after recrystallization.

  A plurality of steel plates with the second layer attached are rolled and rolled, and recrystallized by heat treatment to integrate the stacked steel plates into a laminated steel plate, and the {222} plane integration degree of the laminated steel plate It was clarified that can be improved significantly. The {222} plane integration degree is remarkably increased and the workability is improved, and the laminated layers are oriented and in contact with the same {222} plane, so that it is difficult to peel off at the lamination interface. High workability that was not possible was achieved. Furthermore, by selecting the type of each layer of the laminated steel sheet, the high strength, improved skin roughness resistance, and improved corrosion resistance have been realized.

  The laminated steel sheet of the present invention is a laminated steel sheet in which a plurality of steel sheets made of one or both of carbon steel and alloy steel are laminated and integrated, and an αFe phase at both the surface of the steel sheet surface and the thickness center of the laminated steel sheet Alternatively, one or both of the {222} plane integration degree with respect to the steel sheet surface of one or both of the γFe phases is 60% or more and 99% or less or the {200} plane integration degree is 0.01% or more and 15% or less. Since multiple steel plates are oriented and stacked to integrate, by selecting the type of each layer of the laminated steel plates, high workability that has never been achieved, high strength, improved skin roughness resistance, and corrosion resistance This can be realized together. One or both of carbon steel and alloy steel can be selected as the steel plate of each layer. This is because the steel plates normally used as steel plates for automobiles and steel plates for household appliances are carbon steel and alloy steel.

  The above-mentioned integration in the present invention is a state in which the layers of the laminated steel plates are oriented as described above and are directly metal-bonded to each other. The effect of the present invention cannot be obtained with a laminated steel sheet obtained by preparing a plurality of oriented steel sheets of Patent Document 8 or 9 and pasting or brazing each with an adhesive.

  Each steel plate constituting the laminated steel plate of the present invention is composed of one or both of an αFe phase and a γFe phase. The αFe phase is an Fe crystal phase having a body-centered cubic structure, and includes those in which other atoms partially substitute for Fe or penetrate between Fe atoms. The γFe phase is an Fe crystal phase having a face-centered cubic structure, and includes those in which other atoms partially substitute for Fe or penetrate between Fe atoms.

  In the laminated steel sheet of the present invention, the {222} plane integration degree is 60% or more and 99% or less or the {200} plane integration degree is 0.01% or more and 15% or less of one or both of the αFe phase and the γFe phase with respect to the steel sheet surface. It is characterized by being one or both of the above. If the {222} plane integration degree is low and the {200} plane integration degree is high, breakage and cracking are likely to occur during press working and deep drawing, but the {222} plane integration degree is 60% or more or {200 } If the degree of surface integration is less than 15%, good workability can be realized. On the other hand, when the {222} plane integration degree exceeds 99% and the {200} plane integration degree is less than 0.01%, the workability effect is saturated. Therefore, the {222} plane integration degree is 60% or more and 99% or less, or the {200} plane integration degree is 0.01% or more and 15% or less. When the degree of surface integration is within the range of the present invention, the average r value, which is an evaluation value for drawing, is 2.5 or more, and excellent workability can be obtained.

Here, the measurement of the degree of surface integration can be performed by an X-ray diffraction method using MoKα rays. The {222} plane integration degree and {200} plane integration degree of the αFe phase are obtained as follows. 11 α-faces of Fe crystal parallel to the sample surface {110}, {200}, {211}, {310}, {222}, {321}, {411}, {420}, {332}, { The integral intensities of 521} and {442} were measured, and each of the measured values was divided by the theoretical integral intensity of the sample having a random orientation, and then the ratio of {200} or {222} intensity was determined as a percentage. This is expressed, for example, by the following expression (1) in the {222} intensity ratio.
{222} plane integration degree = [{i (222) / I (222)} / {Σi (hkl) / I (hkl)}] × 100 (1)
However, the symbols are as follows.
i (hkl): Measured integrated intensity of {hkl} plane in the measured sample I (hkl): Theoretical integrated intensity of {hkl} plane in the sample with random orientation Σ: Sum of the α-Fe crystal 11 plane

Similarly, the {222} plane integration degree and {200} plane integration degree of the γFe phase are obtained as follows. Integral intensity of Fe γ crystal 6 planes {111}, {200}, {220}, {311}, {331}, {420} parallel to the sample surface is measured, and each of the measured values is randomly oriented. Then, the ratio of {200} or {222} intensity was obtained as a percentage. This is expressed, for example, by the following formula (2) in the {222} intensity ratio.
{222} plane integration degree = [{i (222) / I (222)} / {Σi (hkl) / I (hkl)}] × 100 (2)
However, the symbols are as follows.
i (hkl): Measured integrated intensity of {hkl} plane in the measured sample I (hkl): Theoretical integrated intensity of {hkl} plane in the sample with random orientation Σ: Sum of six faces of γ-Fe crystal

  Here, regarding the αFe crystal grains, the {222} plane integration degree can also be obtained separately by EBSP (Electron Backscattering Diffraction Pattern) method. The {222} area ratio with respect to the total area of the crystal plane that can be measured by the EBSP method is the {222} integration degree. Therefore, the {222} plane integration degree of the laminated steel sheet of the present invention is 60% or more and 98% or less also by the above method. In the present invention, it is not necessary that the values obtained by all the analysis methods satisfy the specified range of the present invention, and the effect can be obtained if the values obtained by one analysis method satisfy the specified range of the present invention. It is.

  Further, in the EBSP method, the {222} plane shift occurs with respect to the steel plate surface, but the shift is preferably within 30 °. It is more preferable that the deviation of the {222} plane is observed in the L cross section, and the area ratio of crystal grains in which the deviation of the {222} plane in the L cross section is 30 ° or less is 80 to 99.9%. More preferably, the area ratio of crystal grains having a deviation of {222} plane in the L cross section of 0 to 10 ° is 40 to 98%.

The average r value means an average plastic strain ratio obtained by JIS Z 2254, and is a value calculated by the following formula.
Average r value = (r ₀ + 2r ₄₅ + r ₉₀ ) / 4 (3)
R ₀ , r ₄₅ , and r ₉₀ are plastic strain ratios obtained by measuring the test pieces in the 0 °, 45 °, and 90 ° directions with respect to the rolling direction of the plate surface.

  Here, the integrated intensity of a sample having a random orientation may be obtained by preparing a sample and actually measuring it.

  The carbon steel that can be used in the present invention is not particularly limited, and examples thereof include extremely low carbon steel, low carbon steel, medium carbon steel, high carbon steel, and ultra high carbon steel (carbon content of 1.6% or more). It is done. In particular, the carbon steel is preferably at least one of ultra-low carbon steel, low carbon steel, medium carbon steel, or high carbon steel. By using an ultra-low carbon steel having a carbon concentration of several tens of ppm or less, excellent deep drawability like that of a steel plate for automobiles can be realized. By using the low carbon steel, it is possible to realize higher yield strength and superior deep drawability than the ultra low carbon steel. By using medium carbon steel, high tensile strength and excellent deep drawability can be realized. By using high carbon steel, high wear resistance and excellent deep drawability can be realized.

  Although alloy steel which can be used for this invention is not specifically limited, For example, stainless steel, chromium molybdenum steel, manganese molybdenum steel etc. are mentioned. Further, the alloy steel may be any of low alloy steel, medium alloy steel, and high alloy steel. In particular, the alloy steel is preferably stainless steel. By making the steel plate which comprises the outermost surface of a laminated steel plate into stainless steel, it can be set as the steel plate provided with the outstanding corrosion resistance.

  If the laminated steel sheet with a high {222} plane integration degree is composed of three layers, both surfaces are made of stainless steel and the inside is made of ultra-low carbon steel, the press formability and deep drawing of the laminated steel sheet will depend on the characteristics of the inside ultra-low carbon steel. The corrosion resistance of the laminated steel sheet can be realized by the stainless steel on both surfaces. Depending on the requirements of press formability, deep drawability, and steel plate strength, the internal steel plate may be replaced with ultra-low carbon steel to be low carbon steel, medium carbon steel, or high carbon steel. If the laminated steel sheet has two layers and one is made of stainless steel and the other is made of extremely low carbon steel (or low carbon steel, medium carbon steel, high carbon steel), only one of the steel sheets can have high corrosion resistance.

  Normally, the rough skin resistance is better when the crystal grain size of the steel sheet is smaller, but if the crystal grain size becomes smaller, the deep drawability deteriorates. Therefore, in the production process of the laminated steel sheet of the present invention, when a plurality of steel sheets are laminated, if the steel grain size is smaller than the crystal grain diameter of the steel sheet disposed at the center part, The surface roughness is borne by the steel sheet disposed on the surface, and the deep drawability is borne by the steel sheet disposed in the center of the surface, whereby a laminated steel sheet having both excellent skin resistance and deep squeezability can be obtained. By applying a conventionally known method such as increasing the content of C, Ti, Mn, Si, etc. of the steel sheet before the second layer is deposited, for example, the steel sheet with a small crystal grain size arranged on both surface layers. Can be manufactured.

  The steel plate of each layer constituting the laminated steel plate preferably has an Al content of less than 6.5% by mass. When the Al content is less than 6.5% by mass, a high {222} plane texture can be easily obtained as compared with a higher Al content, the tensile breaking elongation is improved, and the high {222} This is because it has a degree of surface integration and sufficient workability can be obtained.

  Compared with adjacent steel sheets, Al, Co, Cu, Cr, Ga, Hf, Hg, In, in part or all of both surfaces of the laminated steel sheets and laminated steel sheets constituting the laminated steel sheets of the present invention It is preferable that one or more elements among Mn, Mo, Nb, Ni, Pb, Pd, Pt, Sb, Si, Sn, Ta, Ti, V, W, Zn, Zr, and the like are concentrated. Particularly preferred elements are one or more of Al, Ni, Si, Sn, V, Zn. Even if the element is strongly processed, it is easy to obtain high processability without causing separation at the laminated interface.

  The thickness of the laminated steel sheet of the present invention is not particularly limited, but is preferably 5 μm or more and 10 mm or less from the viewpoint of production. If the thickness of the laminated steel sheet is too thin, the production yield may decrease, but if the thickness is 5 μm or more, it can be produced without causing such a problem. The steel plate described in Patent Document 9 had a maximum thickness value of 5 mm. In the present invention, the maximum thickness of the steel plates constituting each layer of the laminated steel plates without reducing the {222} plane integration degree is 5 mm. If the steel plate thickness of each layer is 5 mm or less, the maximum value of the distance between the second layers formed on the laminated steel plate after rolling is also 5 mm or less. Therefore, in the heat treatment after rolling, {222 } The degree of surface integration can be sufficiently improved. Since a plurality of such layer steel plates are laminated, the thickness of the laminated steel plates is preferably up to 10 mm for efficient production. If the thickness of the laminated steel sheet is too thick, the {222} plane integration degree may decrease, but if the thickness is 10 mm or less, a laminated steel sheet having no such problem can be obtained.

  In the laminated steel sheet of the present invention, the steel sheets of each layer constituting the laminated steel sheet may be the same type. Since steel plates of the same type are laminated, the quality of the laminated steel plates is equivalent to that of single-layer steel plates having the same thickness. Conventionally, as disclosed in Patent Document 9, a maximum thickness of 5 mm has been a limit for a single-layer steel sheet having a high degree of {222} plane integration. On the other hand, in the present invention, since it is possible to obtain a thick steel plate exceeding 5 mm and reaching 10 mm, it has become possible for the first time to meet the demand for workability improvement in a thick steel plate exceeding 5 mm. In the laminated steel sheets of the present invention in which the steel sheets of the respective layers are of the same type, cross-sectional structure observation in the thickness direction can be used as means for confirming that the steel sheets are laminated steel sheets. In addition, as a means for confirming that it is a laminated steel sheet, the laminated steel sheet of the present invention manufactured by superposing and rolling the steel sheet with the second layer adhered to the laminated surface, and then performing a heat treatment process. The cross-sectional structure observation in the plate thickness direction can be used. Each steel plate to be overlaid always passes through the second layer. Even after the second layer is uniformly diffused and laminated by heat treatment, the crystal grain boundary near the portion where the second layer existed before the heat treatment has a linear shape. By observing the shape of the crystal grains by the means for observing the metal structure, it is possible to easily determine whether or not they are laminated and integrated.

  Next, the manufacturing method of the laminated steel plate of this invention is demonstrated.

  A plurality of steel plates having a thickness of 10 μm or more and 10 mm or less are prepared, and the second layer is attached to at least one side of a part or all of the plurality of steel plates. The second layer is a metal whose main component is other than Fe. By laminating the plurality of steel plates, rolling the superposed steel plates and then recrystallizing by heat treatment, and simultaneously laminating each steel plate, the laminated steel plate having a high degree of {222} plane integration of the present invention Can be manufactured.

  The plate thickness of the steel plates before lamination is 10 μm or more and 10 mm or less. If the plate thickness is less than 10 μm, handling at the time of stacking becomes complicated and the yield decreases. On the other hand, if the plate thickness before lamination exceeds 10 mm, the {222} plane integration degree of the laminated steel plate is lowered.

  In order to obtain a high degree of {222} plane integration, it is essential to perform rolling in a state in which the second layer is attached to at least one side of a part or all of the steel plates of each layer constituting the laminated steel plate. Under the present circumstances, when these steel plates after adhering a 2nd layer are piled up, it is preferable if the 2nd layer is formed in all the contact surfaces of each steel plate. Therefore, even if the steel plates to which the second layer is not attached before the superposition are included, they may be superposed so as to contact the second layer of the steel plates that are adjacent to each other after the superposition. Furthermore, it is preferable that the second layer is formed on both outermost surfaces of the stacked steel plates. Here, the second layer is a metal whose main component is other than Fe. If Fe is the main component, the high {222} plane integration degree of the present invention cannot be realized. Here, the main component other than Fe means that the total content of metal components other than Fe is 90% by mass or more.

  The adhesion of the second layer to the steel sheet can be performed by a hot dipping method, an electroplating method, a dry process method, a clad method or the like, and the effect of the present invention can be obtained by any method. It is also possible to add a desired alloy element to the second layer to be deposited and to alloy it at the same time.

  At least two steel plates to which the second layer is attached are overlapped. When the number of stacked steel plates increases, the steel plates are liable to shift during rolling. In order to suppress this deviation, it is only necessary to temporarily weld several surrounding points. Or pack rolling which wraps and rolls in metal containers, such as mild steel, may be used. The number of sheets to be superposed is more preferably a number in which the thickness of the superposed steel sheets after rolling the superposed steel sheets at a predetermined rolling rate falls within a range of 5 μm to 10 mm.

  Further, the rolled steel sheets are cold-rolled or warm-rolled. The rolling rate is preferably 30% or more and 95% or less. If the rolling rate is too low, the {222} plane integration degree of the laminated steel sheet obtained after the heat treatment step may not be sufficiently obtained, but if it is 30% or more, a sufficient {222} plane integration degree can be obtained. it can. If the rolling rate exceeds 95%, the increase in {222} plane integration is saturated, and the rolling cost increases, so that the industrial merit may be lowered. In cold rolling, the accumulation of strain energy increases, so recrystallization in the subsequent heat treatment process effectively proceeds. When warm rolling is performed at several tens of degrees Celsius to about 600 degrees Celsius, accumulation of strain energy is reduced, but adhesion between the stacked steel sheets is improved, and integration in the subsequent heat treatment process is further promoted. effective.

  In subsequent steps, it is necessary to recrystallize by heat treatment. As a result of attaching a second layer mainly composed of a metal other than Fe to the contact surface of each layer of the stacked steel sheets, rolling in that state, and recrystallizing by heat treatment, a laminated steel sheet is obtained, Each layer of the laminated steel sheet has a high degree of surface integration. In that case, the effect of diffusing the elements contained in the second layer into the steel is also included. When the elements contained in the second layer are diffused in the steel, a higher {222} plane integration degree tends to be obtained, and high-temperature oxidation resistance and mechanical properties are also improved.

The heat treatment step responsible for recrystallizing the steel sheet can be performed in a non-oxidizing atmosphere such as a vacuum atmosphere, an Ar atmosphere, an H ₂ atmosphere, or a helium atmosphere. At this time, the heat treatment temperature is preferably 600 ° C. or more and 1200 ° C. or less. If it is lower than 600 ° C., the {222} plane integration degree is low, and the range of the present invention may not be reached. Moreover, if it is a temperature range of 600-1000 degreeC, 30 second or more is desirable for heat processing time. If the temperature is 1000 ° C. or less and the heat treatment time is less than 30 seconds, the {222} plane integration degree is low, and the range of the present invention may not be reached. When the heat treatment temperature is higher than 1000 ° C., there is no limitation on the heat treatment time, and a high {222} surface density can be obtained. In particular, if it exceeds 1000 ° C., the {222} plane integration degree can be easily increased even if the heat treatment time is 30 seconds or less. If the heat treatment temperature is higher than 1200 ° C., the heat treatment equipment cost increases, and the industrial merit may be reduced.

  Next, a preferable temperature increase rate during the heat treatment is 1 ° C./min or more and 1000 ° C./min or less. When the rate of temperature rise is 1000 ° C./min or less, a higher {222} plane integration degree can be easily obtained. Further, when the temperature is 1 ° C./min or more, the productivity can be improved in each stage. Therefore, the preferable range of the temperature rising rate is 1 ° C./min or more and 1000 ° C./min or less.

  Each steel sheet adjacent to the second layer is alloyed, and the {222} plane integration degree of one or both of the αFe phase and the γFe phase with respect to the steel sheet surface is 60% or more and 99% or less, or the {200} plane integration degree is 0. A laminated steel sheet having a high {222} plane integration degree, characterized by being one or both of 0.01% or more and 15% or less, is included in the laminated steel sheet of the present invention. If the {222} plane integration degree is less than 60% and the {200} plane integration degree is 15% or more, cracks and fractures are likely to occur during drawing, bending, and rolling. Further, when the {222} plane integration degree exceeds 99% and the {200} plane integration degree is less than 0.01%, the effect is saturated and the manufacture becomes difficult.

  In the present invention, regarding the thickness of each of the second layers attached to the base material before cold rolling, a more desirable range is 0.05 μm or more and 1000 μm or less. When the steel sheet and the second layer are alloyed, the alloyed thickness is included in the thickness of the second layer. Moreover, when the 2nd layer has adhered to both surfaces, it is the sum total of the thickness of both surfaces. If the thickness of the second layer is less than 0.05 μm, the {222} plane integration degree may be lowered, and the possibility of not falling within the scope of the present invention is increased, so 0.05 μm or more is preferable. Even if it exceeds 1000 μm, the {222} plane integration degree may be lowered, and the possibility of not falling within the scope of the present invention is increased, so 1000 μm or less is preferable.

  In the present invention, the second layer is a metal whose main component is other than Fe. More desirable elements constituting the second layer are Fe, Al, Co, Cu, Cr, Ga, Hf, Hg, In, Mn, Mo, Nb, Ni, Pb, Pd, Pt, Sb, Si, Sn, Ta , Ti, V, W, Zn, and Zr, and one of the elements shown on the left, excluding Fe, as a main component. Here, the main component is any element other than Fe among the elements shown on the left means that the total content of components other than Fe among the elements shown on the left is 90% by mass or more. Particularly preferable elements are one or more elements of Al, Ni, Si, Sn, V, and Zn. For example, as the second layer, an Al alloy such as Al—Si, a Zn alloy such as Zn—Al, a Sn alloy such as Sn—Ni, or the like is specifically selected. These elements have the effect of effectively accumulating strain energy when rolling stacked steel sheets. Further, by promoting the alloying between adjacent steel plates, there is an effect of making it easier to integrate the stacked steel plates.

  When it is assumed that all the components contained in the second layer are uniformly diffused in the laminated steel plate, the total of the components excluding Fe among the components contained in the second layer is 0.5% by mass or more in the laminated steel plate. An amount is preferable. Thereby, the {222} plane integration degree of a laminated steel plate can fully be raised. On the other hand, if the total concentration in the steel sheet of the components excluding Fe among the components contained in the second layer is too high, the elongation at break of the steel sheet may be reduced, and the press formability may deteriorate. If the concentration in the steel sheet is 6.5% by mass or less, occurrence of such a problem can be prevented.

  Here, when Al is contained in the second layer, the desirable Al content of the base steel plate is less than 3.5% by mass. When the Al concentration of the base steel sheet is 3.5% by mass or more and heat treatment is performed with the Al alloy attached to the second layer, shrinkage may occur during the heat treatment and the dimensional accuracy may be significantly reduced. Therefore, in the present invention, when Al is contained in the second layer, the more preferable Al content of the base steel plate is less than 3.5% by mass.

  Next, when Al is not contained in the second layer, the Al content as a base material is set to less than 6.5% by mass within the scope of the present invention. Fe, Co, Cu, Cr, Ga, Hf, Hg, In, Mn, Mo, Nb, Ni, Pb, Pd, Pt, Sb, Si, Sn, Ta, Ti, V, W as a second layer on at least one side In the case where the step of attaching one or more elements of Zn and Zr is included, when the Al content of the base steel plate is 6.5% by mass or more, the tensile elongation at break of the obtained steel plate decreases. In some cases, sufficient workability cannot be obtained even with a high {222} plane integration degree. Therefore, the more preferable Al content of the base material steel plate in this case is set to less than 6.5% by mass.

  In the manufacturing method of the present invention, the thickness of a plurality of steel plates to be prepared (also referred to as “base material steel plates”) is 10 μm or more and 10 mm or less. When the thickness of the steel sheet is less than 10 μm, the production yield after cold rolling is lowered, so that it is not suitable for practical use. If it exceeds 10 mm, the {222} plane integration degree does not fall within the scope of the present invention. Therefore, the thickness of the steel plate to be prepared is 10 μm or more and 10 mm or less.

  In order to exhibit the further excellent effect of the present invention, it is preferable to perform a preliminary heat treatment on the base steel plate before the second layer is deposited. This preliminary heat treatment rearranges the dislocation structure accumulated in the manufacturing process of the base steel sheet, and it is desirable to cause recrystallization, but it is not always necessary to cause recrystallization.

  Here, a desirable preliminary heat treatment temperature is 700 ° C. or higher and 1100 ° C. or lower. When the temperature is lower than 700 ° C., there is a case where the change of the dislocation structure for obtaining the superior effect of the present invention hardly occurs. When the temperature exceeds 1100 ° C., an unfavorable oxide film is formed on the surface of the steel sheet, which may adversely affect the subsequent adhesion of the second layer and cold rolling. The pre-heat treatment atmosphere can obtain the above-described effect under any conditions in a vacuum, an inert gas atmosphere, a hydrogen atmosphere, or a weakly oxidizing atmosphere. And the conditions which do not form the oxide film of the steel plate surface which has a bad influence on subsequent cold rolling are calculated | required. The time for the preliminary heat treatment does not need to be specifically limited. However, considering the manufacturability of the steel sheet, the time within a few seconds to several hours is appropriate.

  Various laminated steel sheets of the present invention using ultra low carbon steel, low carbon steel, medium carbon steel, high carbon steel A, high carbon steel B, stainless steel, manganese molybdenum steel having the composition shown in Table 1 as the steel sheets before lamination. Manufactured. The second layer element was adhered to both surfaces of the steel sheet before lamination, laminated, cold rolled, and then heat treated.

  Hereinafter, for Examples 1 to 6, the steel type of the steel sheet before lamination, the thickness of the steel sheet before adhesion of the second layer before lamination, the second layer element, the thickness of the second layer, the number of laminations, cold rolling in cold rolling after lamination The conditions shown in Tables 2 to 7 were employed for the rate, the heat treatment temperature of the heat treatment after rolling, the time, and the plate thickness of the laminated steel sheet after the rolling and heat treatment. Numerical values that fall outside the scope of the present invention are underlined.

  A second layer was adhered to both surfaces of each steel plate before lamination. In Tables 2 to 7, “second layer thickness” indicates the amount of adhesion on one side. The value shown in parentheses in the “second layer thickness” column of each table (for example, (+ 2.9% Al)) is the result of the diffusion of the main elements of the second layer into the steel plate, and the component content of the steel plate It is a numerical value indicating the amount of increase. The value indicated in parentheses in “Number of layers” is a numerical value indicating the total thickness including the second layer after lamination and before rolling, and the unit is mm.

  About the laminated steel plate which completed to heat processing, {222} plane integration degree and {200} plane integration degree of each surface and thickness center were evaluated. The measurement of the surface integration degree was performed by the X-ray diffraction by MoKα ray using the procedure as described above. Here, the surface means the penetration depth of the X-ray from the surface of the steel plate surface. The center of the plate thickness was etched to a depth of 1/2 t of a steel plate having a plate thickness t, and X-ray diffraction measurement was performed.

In addition, the Rankford value was evaluated based on the average r value obtained by the equation (3).
Moreover, regarding the presence or absence of peeling at the laminated interface after processing, the steel sheet was bent 180 degrees at 0 T, and the cross section of the bent portion was observed with an electron microscope to examine the presence or absence of peeling at the laminated interface.

(Example 1)
Laminated steel sheets were manufactured under the conditions shown in Table 2. As the steel sheet to be laminated, any single steel type of ultra low carbon steel, low carbon steel, medium carbon steel, high carbon steel A, high carbon steel B, manganese molybdenum steel, or stainless steel was selected. Since the laminated steel plates are laminated with steel plates of a single steel type, they can be used as steel plates of a single steel type even after lamination.

  As an adhesion method of the second layer element, Al-10 mass% Si adopted a hot dipping method, Al adopted ion plating, and Zn-6% Ni adopted a hot dipping method.

  Invention Examples 2 to 5, 7, 10, 13 to 14, and 16 to 18 are all laminated steel sheets of the present invention, and the {222} plane integration degree is as good as 60% or more over the entire thickness of the laminated steel sheets. A high degree of surface integration was achieved.

  In Comparative Examples 1, 6, 11, 12, and 15, the number of laminated layers is 1, that is, a single-layer steel plate, and therefore the {222} plane integration degree is lower than that of the present invention example. As a result, the r value is low, that is, the processability is poor. Comparing Comparative Example 1 and Inventive Example 2 in which the base steel plate, second layer element, rolling rate, heat treatment temperature, time, and final thickness are all the same, the inventive example 2 shows {222} plane integration degree On the other hand, in Comparative Example 1, the {222} plane integration degree at the central portion of the plate thickness was a low value of less than 60%. In a single-layer steel plate, it becomes difficult to effectively form a special dislocation structure formed in the steel plate during rolling to the vicinity of the center of the plate thickness. As a result, a {222} plane formed from the dislocation structure by heat treatment This is probably because the frequency of recrystallized nuclei having a decrease was reduced.

  In Comparative Example 8, the number of laminated layers is 4, but the heat treatment temperature is out of the scope of the present invention, and therefore the {222} plane integration degree is low at less than 60% for both the surface of the steel plate and the center of the plate thickness. As a result, the r value was low, and further peeling occurred at the lamination interface by processing. Comparative Example 9 is a laminated steel sheet that has not been provided with the second layer, but the {222} plane integration degree is a low value of less than 60% for both the surface of the steel sheet surface and the center part of the plate thickness. It was low, and further peeling occurred at the lamination interface by processing.

  The r value (Rankford value) of the laminated steel sheet of the example of the present invention was a good value of 2.5 or more.

(Example 2)
Laminated steel sheets were manufactured under the conditions shown in Table 3. About the invention examples 21-26, the steel plate laminated | stacked used stainless steel for the outermost surface, and used ultra-low carbon steel for the inside. Since the laminated steel sheet of Invention Example 21 is formed by laminating steel sheets of a single steel type, it can be used as a steel sheet of a single steel type even after lamination.

  As a method for attaching the second layer element, Al-10 mass% Si was attached by a hot dipping method.

  Invention Examples 21 to 26 are all laminated steel sheets according to the present invention, and the {222} plane integration degree was 60% or more over the entire thickness of the laminated steel sheets, and a good level integration degree could be realized.

  All the Rankford values of the laminated steel sheets were good values of 2.5 or more.

  As a corrosion test, a one-month outdoor air exposure test was conducted. Since Invention Examples 22 to 26 are laminated steel plates having stainless steel on both surfaces, no corrosion occurred. On the other hand, in the inventive example 21, since the ultra-low carbon steel was exposed on the surface, rust was generated on the entire surface.

(Example 3)
Laminated steel sheets were manufactured under the conditions shown in Table 4. Al, Mo, Ni, Si, Sn, V, and Zn were used as the second layer. As the base steel sheet to be laminated, a single steel type of either ultra low carbon steel or low carbon steel was selected. Since the laminated steel plates are laminated with steel plates of a single steel type, they can be used as steel plates of a single steel type even after lamination.

  As a method for attaching the second layer element, Al, Sn, and Zn employ a hot dipping method, Ni employs an electroplating method, and Mo, Si, and V employ ion plating.

  Invention Examples 31 to 37 are all laminated steel sheets according to the present invention, and a {222} plane integration degree of 60% or more was able to be realized.

  The Rankford value of the laminated steel sheet of the present invention was a good value of 2.5 or more.

  About the example of the present invention which selected medium carbon steel as a steel plate before lamination, the tensile strength was a high value compared with the example of the present invention which selected ultra-low carbon steel.

Example 4
Laminated steel sheets were manufactured under the conditions shown in Table 5. The thickness of the laminated steel sheet after cold rolling and heat treatment was changed from 4 μm to 11.8 mm. As the base steel sheet to be laminated, a single steel type of either ultra low carbon steel or low carbon steel was selected. Since the laminated steel plates are laminated with steel plates of a single steel type, they can be used as steel plates of a single steel type even after lamination.

  As a method for attaching the second layer element, Al-10 mass% Si was attached by a hot dipping method.

  Invention Examples 41 to 49 and 51 are all laminated steel sheets according to the present invention, and a {222} plane integration degree of 60% or more was able to be achieved. In particular, with respect to Inventive Examples 47 to 49, 51, a {222} degree of integration of 60% or more can be realized regardless of whether the laminated steel sheet after rolling and heat treatment is a very thick steel sheet of 5 mm or more. It was. With respect to Inventive Example 41, the thickness of the laminated steel sheet after rolling and heat treatment was less than 5 μm, which is the lower limit of the good range of the present invention, resulting in a decrease in yield during production. With respect to Inventive Example 42, since the laminated steel plate thickness after rolling and heat treatment was as thin as 8 μm, the {222} plane integration degree and the {200} plane integration degree at the center of the plate thickness were the same values as the surface, respectively. . In Invention Example 51, since the thickness of the laminated steel sheet after rolling and heat treatment exceeds 10 mm, the {222} plane integration degree is not large, but it is within the scope of the present invention, and good workability (Rankford) Value).

  For Comparative Example 50, the {222} plane integration degree was less than 60%, a high Rankford value was not obtained, and peeling was observed at the laminated interface after processing.

  The Rankford value of the laminated steel sheet of the inventive example was a good value of 2.5 or more.

(Example 5)
Laminated steel sheets were manufactured under the conditions shown in Table 6. The plate thickness of the base steel plate before lamination was changed from 8 μm to 10.9 mm. As the base steel sheet to be laminated, a single steel type of either ultra low carbon steel or low carbon steel was selected. Since the laminated steel plates are laminated with steel plates of a single steel type, they can be used as steel plates of a single steel type even after lamination.

  As a method for attaching the second layer element, Al-10 mass% Si was attached by a hot dipping method.

  Invention Examples 61 to 67 are all laminated steel sheets according to the present invention, and a {222} plane integration degree of 60% or higher was able to be realized. With regard to Inventive Example 41, the plate thickness of the steel plate before lamination was 8 μm and less than 10 μm, which is the lower limit of the preferred range, so that the lamination process such as deviation prevention was complicated when the steel plates before lamination were laminated.

  For Comparative Example 68, the base steel plate thickness before lamination exceeds 10 mm, the {222} plane integration degree is less than 60%, and good workability cannot be obtained (low Rankford value). Peeling was observed at the laminated interface.

  The Rankford value of the laminated steel sheet of the present invention was a good value exceeding 2.5.

(Example 6)
Laminated steel sheets were manufactured under the conditions shown in Table 7. As the base steel sheet to be laminated, a single steel type of either ultra low carbon steel or low carbon steel was selected. Since the laminated steel plates are laminated with steel plates of a single steel type, they can be used as steel plates of a single steel type even after lamination.

  Al, Al-10 mass% Si, and Zn were selected as the second layer, and the adhesion thickness of the second layer was changed from 0.03 μm to 1040 μm. As an adhesion method of the second layer element, Al adopted ion plating, Al-10 mass% Si, and Zn adopted a hot dipping method.

  Invention Examples 72 to 78, 81 to 84, and 86 are all laminated steel sheets of the present invention, and a {222} plane integration degree of 60% or more was able to be achieved.

  Regarding the thickness of the second layer, the example of the present invention in the range of 0.05 μm or more and 1000 μm or less has a higher {222} plane integration degree and excellent workability (high Rankford value).

  The Rankford value of the laminated steel sheet of the present invention was a good value of 2.5 or more.

(Example 7)
Laminated steel sheets were produced under the conditions shown in Table 8 for the purpose of improving the rough skin resistance. As the base steel plates to be laminated, medium carbon steel was selected for both surfaces, and four layers of extremely low carbon steel were selected for the inner layer.

  Al-10 mass% Si was selected as the second layer, and the thickness of the second layer was 24 μm (very low carbon steel) and 10 μm (medium carbon steel), and the second layer was adhered to both surfaces of each steel plate. The hot dipping method was adopted as the second layer element adhesion method.

  Invention Example 91 is a laminated steel sheet according to the present invention, and a {222} plane integration degree of 60% or more was able to realize a good plane integration degree.

  The Rankford value of the laminated steel sheet was a good value of 2.5 or more.

  When the crystal grain size of the steel sheet was evaluated, the crystal grain size of the medium carbon steel part on both surfaces was about 2/3 of the crystal grain size of the internal ultra-low carbon steel part.

  Using the present invention example 91 shown in Table 8 and the 0.6 mm thick laminated steel sheet shown in the invention example 2 of the example 1, a test for evaluating the rough skin resistance was conducted. In the evaluation method, a cup having a diameter of 30 mm was formed at a drawing ratio of 3.0, and the presence or absence of rough skin (orange peel) was visually examined. As a result, in Example 91 of the present invention, there was no rough skin, whereas in Example 2 of the present invention, orange peel was slightly generated near the bottom of the cup, although the level of the product was not affected.

Claims (12)

  A laminated steel plate in which a plurality of steel plates made of one or both of carbon steel and alloy steel are laminated and integrated, and one or both of the αFe phase and the γFe phase in both the steel plate surface and the thickness center of the laminated steel plate A laminated steel sheet, wherein the {222} plane integration degree relative to the steel sheet surface is one or both of 60% or more and 99% or less or the {200} plane integration degree relative to the steel sheet surface is 0.01% or more and 15% or less.   The laminated steel sheet according to claim 1, wherein the carbon steel is at least one of ultra-low carbon steel, low carbon steel, medium carbon steel, or high carbon steel.   The laminated steel sheet according to claim 1 or 2, wherein the alloy steel is stainless steel.   The laminated steel sheet according to any one of claims 1 to 3, wherein the steel sheet of each layer constituting the laminated steel sheet is a steel sheet having an Al content of less than 6.5 mass%.   Compared with each adjacent layer steel plate, one or more elements of Al, Ni, Si, Sn, V, and Zn are present in a part or all of both surfaces of the laminated surface of each layer steel plate and the laminated steel plate constituting the laminated steel plate. The laminated steel sheet according to any one of claims 1 to 4, wherein the laminated steel sheet is concentrated.   The laminated steel sheet according to any one of claims 1 to 5, wherein the thickness of the laminated steel sheet is 5 µm or more and 10 mm or less.   The laminated steel sheet according to any one of claims 1 to 6, wherein the steel sheets of each layer constituting the laminated steel sheet are of the same type. Preparing a plurality of steel plates having a thickness of 10 μm or more and 10 mm or less,
At least one side of a part or all of the plurality of steel plates is attached with a second layer of a metal whose main component is other than Fe,
Laminating the plurality of steel plates;
Rolling the laminated steel sheet;
Then recrystallize by heat treatment and at the same time integrate the laminated steel sheet,
The manufacturing method of the laminated steel plate characterized by the above-mentioned.   The method for producing a laminated steel sheet according to claim 8, wherein the thickness of the second layer to be adhered is 0.05 µm or more and 1000 µm or less.   The second layer includes Fe, Al, Co, Cu, Cr, Ga, Hf, Hg, In, Mn, Mo, Nb, Ni, Pb, Pd, Pt, Sb, Si, Sn, Ta, Ti, V, 10. The method for producing a laminated steel sheet according to claim 8, comprising one or more elements of W, Zn, and Zr, and comprising as a main component any element of the left elements other than Fe. .   The method for producing a laminated steel sheet according to any one of claims 8 to 10, wherein the second layer contains Al, and the plurality of prepared steel sheets have an Al content of less than 3.5 mass%. .   11. The production of a laminated steel sheet according to claim 8, wherein the second layer does not contain Al, and the plurality of prepared steel sheets have an Al content of less than 6.5% by mass. Method.